• 한국약용작물학회지
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• 제2권2호
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• pp.154-161
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• 1994

폐모(Fritillaria thunbergii)의 자구인편, 줄기, 및 마디조직 및 정단을 구명하고자 실험한 결과는 다음과 같다. 1. 자구형성수는 자구인편조직에 비해 마디나 줄기조직에서, BA처리구보다 kinetin처리구에서 현저히 증가하였다. 줄기조직은 생장이 3cm이하일 때 채취하여 kinetin이 $1.0{\sim}3.0mg\;/L$첨가된 배지에 배양하였을 , 마디조직은 3cm이상 생장한 조직을 kinet이 5.0mg /L 첨가된 배지에 배양하였을 때 자구형성수가 증가하였다. 기내에서 생장한 마디의 액아에서 자구가 직접 형성되는 현상도 관찰되었는데 최고 15개의 자구가 마디에서 형성되었다. 2. 신초가 l0cm 이상 생장한 후 줄기조직을 채취하여 배양하였을 때는 어린 줄기조직보다 자구 형성능력이 감소하였으며 생장조절제의 첨가가 자구형성에 필수적이었고 적정농도는 kinetin 1.0 mg /L였다. 3. 지하에서 생장중인 패모에서는 줄기조직이나 정단이나 자구조직에 비해 구형성율이 높았으며 자구 형성에 적합한 당의 농도는 $5{\sim}7%$였다. 4. 이상의 결과를 종합해 보면 패모의 기내 배양재료로는 자구 인편조직에 비해 3cm정도 생장한 줄기나 마디조직을 이용하는 것이 대량중식에 효과적일 것으로 생각되었다. 특히 줄기나 마디조직은 구형성수가 최고 20배 이상 달하여 중식율이 상당히 높았다. 생장조절제 요구도는 배양재료에 따라 다소 차이가 있으나 Kinetin $1.0{\sim}5.0mg\;/L$가 적합하였다.

• 한국자원식물학회지
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• 제32권3호
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• pp.237-243
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• 2019

Soybean is the one of recalcitrant legume species for shoot induction. Shoot regeneration via direct organogenesis was investigated in five soybean cultivars, 'Dawon', 'Pungsan', 'Daewon', 'Taekwang' and 'Chongdoo 1' by using cotyledonary node explants. Out of 5 soybean cultivars, an efficient shoot regeneration condition was developed in the two soybean cultivars, 'Dawon' and 'Pungsan'. When various kinds of plant growth regulators with different concentration were estimated, the optimum medium condition for shoot induction in both soybean cultivars was MS + B5 vitamin supplemented with BA at concentration 2 mg/L. In addition, shoot formation efficiency was increased with 97.09% and 93.88% by the pretreatment of BA onto the explants before in vitro culture in both cultivars. Shoot induction in 'Dawon' cultivar was originated from epidermal tissue and sub-epidermal layers when histological changes were investigated under shoot regeneration after culturing cotyledonary node segments on shoot induction medium for 0 to 21 days. Especially, cell dedifferentiation was observed from parenchyma cells to meristematic cell in 3-day cultured segments.

• Journal of Plant Biotechnology
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• 제8권1호
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• pp.37-41
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• 2006

In vitro mass multiplication of Vanilla planifolia was investigated using node as explant. Multiple shoots were developed in MS medium supplemented with $2.0mgl^{-1}$ 6-benzylaminopurine and $1.0mgl^{-1}$ $\alpha$-naphthalene acetic acid. Multiple shoots were maintained for 6-T weeks with regular subculturing at the end of $3^{rd}$ week onto fresh medium. The maximum number of shoots at the rate of 12.8 per node segment was achieved over a period of four weeks. The elongated shoots were separated from the shoot clusters and were transferred onto half strength MS medium supplemented with indole-3-acetic acid ($1.0mgl^{-1}$) over a period of 28 days for induction of roots. The development of roots was observed on $7^{th}$ day of incubation. The in vitro raised plantlets were transferred to poly-cups, covered with polyethylene sheets and maintained under shade net for 25 days for hardening. Finally these plants were transferred to field and recorded that 85 % of tissue cultured plants were survived. From the present study, a simple and efficient micropropagation protocol was developed for Vanilla planifolia using single node segments as explants.

• 디지털융복합연구
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• 제17권9호
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• pp.153-161
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• 2019

무선 홈 프록시에서 미디어 객체 세그먼트들에 대한 식별은 캐싱 지연에 중요한 영향을 미치게 되며, 캐싱 지연은 프록시의 성능을 떨어뜨리는 원인을 제공한다. 본 논문에서는 홈 네트워크의 프록시 성능을 향상시키고 미디어 객체 세그먼트들에 대한 캐싱 성능을 향상시키기 위하여 SFSC(Single Fetching Smart Caching)전략과 MFSC(Multi-Fetching Smart Caching)전략을 제안한다. SFSC전략은 홈 노드가 요청한 객체 세그먼트를 한 번에 하나씩 순차적으로 패칭하여 캐싱을 수행하는 기법으로서 보다 빠른 캐시 히트율을 보장해 주는 기법이며, MFSC전략은 홈 노드가 요청한 객체 세그먼트를 한 번에 여러 개씩 block화하여 캐시하는 기법으로서 처리율을 향상시키기 위한 기법이다. 시뮬레이션 결과 SFSC기법은 MFSC기법에 비해서 캐시 히트율과 캐싱 지연이 보다 효율적임을 알 수 있었으며, 반대로 객체 세그먼트에 대한 처리율은 MFSC기법이 SFSC기법에 비해서 보다 효율적임을 알 수 있었다.

• 한국통신학회논문지
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• 제22권4호
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• pp.618-636
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• 1997

DQDB(Distributed Queue Dual Bus) protocol, the IEEE 802.6 standard protocol for metropolitan area networks, does not fully take advantage of the capabilities of dual bus architecture. Although fairness in bandwidth distribution among nodes is improved when using so called the bandwidth balancing mechanism, the protocol requires a considerable amount of time to adjust to changes in the network load. Additionally, the bandwidth balancing mechanism leaves a portion of the available bandwidth unused. In a high-speed backbone network, each node may act as a bridge/ router which connects several LANs as well as hosts. However, Because the existence of high speed LANs becomes commonplace, the congestionmay occur on a node because of the limitation on access rate to the backbone network and on available buffer spaces. to release the congestion, it is desirable to install some congestion control algorithm in the node. In this paper, we propose an efficient congestion control mechanism and fair and waster-free MAC protocol for dual bus network. In this protocol, all the buffers in the network can be shared in such a way that the transmission rate of each node can be set proportional to its load. In other words, a heavily loaded node obtains a larger bandwidth to send the sements so tht the congestion can be avoided while the uncongested nodes slow down their transmission rate and store the incoming segments into thier buffers. this implies that the buffers on the network can be shared dynamically. Simulation results show that the proposed probotol significantly reduces the segment queueing delay of a heavily loaded node and segment loss rate when compared with original DQDB. And it enables an attractive high throughput in the backbone network. Because in the proposed protocol, each node does not send a requet by the segment but send a request one time in the meaning of having segments, the frequency of sending requests is very low in the proposed protocol. so the proposed protocol signigificantly reduces the segment queuing dely. and In the proposed protocol, each node uses bandwidth in proportion to its load. so In case of limitation of available buffer spaces, the proposed protocol reduces segment loss rate of a heavily loaded node. Bandwidth balancing DQDB requires the wastage of bandwidth to be fair bandwidth allocation. But the proposed DQDB MAC protocol enables fair bandwidth without wasting bandwidth by using bandwidth one after another among active nodes.

• 한국통신학회논문지
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• 제34권12B호
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• pp.1435-1443
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• 2009

본 논문에서는 에너지 수확 센서 네트워크 시스템을 DEVS 형식론을 이용해서 시뮬레이션하고 모델링한다. 이 시스템은 주전원이나 배터리를 사용하는 싱크(마스터(master)) 노드와 에너지 수확 소자로부터 전원을 공급 받는 센서(slave) 노드로 구성 된다. 시뮬레이션을 위해 (i) 슬레이브 노드에서 에너지 수확하고 저장하는 회로의 동작을 연속적인 구간들로 분할한 후에 각 구간을 이산적인 상태로 표현하고, (ii) 마스터 노드와 슬레이브 노드의 컴포넌트들의 동작의 관계를 면밀하게 분석하여, (iii) 분석된 결과를 DEVS 형식론을 이용하여 모델링하고 시뮬레이션 한다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.16-16
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• 2019

The Cassava (Manihot esculenta Crantz) is a perennial woody shrub cultivated mainly in the tropics for its starchy tuberous roots. It belongs to the family Euphorbiaceae which also includes rubber (Hevea brasiliensis) and castor bean (Ricinus communis). Among tropical crops, rice, sugarcane, maize and cassava are the most important sources of calories for human consumption. Problems in the propagation of cassava are virus diseases and low rates of seed germination. Thus, a study was undertaken to develop an efficient in vitro mass propagation protocol of Manihot esculenta Crantz. Young and actively growing stem segments were excised from adult plants of cassava. Samples were cut into a 3~4 cm nodal segments with single node after sterilization, and cultivated in the different medium supplemented with various plant growth regulators for 4 weeks. For shoot multiplication, single-node stem segments, approximately 1 cm in length, were taken from in vitro derived shoots and subcultured. After 4~6 weeks, the shoot generation rate was 55.6%, the shoot number and its length were 1.0/explant and 2.3 cm in the most favorable medium composition. Our experiments confirmed that in vitro growth and multiplication of plantlets could depend on its reaction to the different medium composition, and this micropropagation techniques could be a useful system for healthy and vigorous plant production.

• 한국수자원학회논문집
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• 제55권spc1호
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• pp.1187-1195
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• 2022

관망의 세그먼트를 파악하기 위한 알고리즘을 구동시키기 위해서는 관망의 주요 구성요소들인 절점, 파이프, 및 밸브 간의 상대적인 위치 관계를 세그먼트 탐색 알고리즘의 입력정보로 준비해야 한다. 실제 지자체 관망에 존재하는 세그먼트를 보다 정확하게 파악하기 위해서는 관망 수리해석 프로그램 구동을 위해 모델링된 관망 정보를 이용하기 보다는, 모든 제수밸브가 포함된 지자체 상수도 관망 GIS/CAD 데이터베이스를 이용하여 세그먼트 탐색에 적합하게 재구성된 관망 정보를 이용할 필요가 있다. 본 연구에서는 지자체 상수도 관망 GIS/CAD 데이터를 이용하여 관망 세그먼트 탐색에 적합한 노드-파이프-밸브 간의 상대적 위치관계를 수립할 수 있는 컴퓨터 계산 알고리즘을 개발하였으며, 이를 구현할 수 있는 MATLAB 프로그램을 개발하였다. 개발된 MATLAB 프로그램을 국내 지자체 상수도 관망에 적용하여 그 실효성을 확인하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.22-25
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• 1999

A dynamic explicit finite element code for simulating sheet forming processes has been developed The code utilises the discrete Kirchhoff shell element and contact force is treated by a conventional penalty method. In order to reduce the computational cost a new and robust contact searching algorithm has been developed and implemented into the code. in the method a hierarchical structure of tool segments called a tree structure is built for each tool at the initial stage of the analysis Tree is built in a way to divide a trunk to 8 sub-trunk 2 in each direction until the lowest level of the tree(leaf) contains exactly one segment of the tool. In order to have a well-balanced tree each box on each sub level contains one eighth of the segments. Then at each time step contact line from a node comes out of the surface of the tool. Simulation of various sheet forming processes were performed to verify the validity of the developed code with main focus on he usefulness of the developed contact searching algorithm.

• 전자통신동향분석
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• 제38권2호
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• pp.36-45
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• 2023

Segment routing (SR) is a source-based routing architecture in which a node steers packets adhering to service and topological requirements. Using programmable segments, SR enables end-to-end service connectivity to satisfy the network constraints of various services. SR can be implemented with both MPLS and IPv6 dataplanes. This survey presents the overview of SR for IPv6 dataplane (SRv6), network programming technologies based on SRv6, and the SR deployment status.